【任务3】阅读P314的例10.1(电子版的在平台上见txt文件)。该例实现了一个复数类,但是美中不足的是,复数类的实部和虚部都固定是double型的。可以通过模板类的技术手段,设计Complex,使实部和虚部的类型为定义对象时用的实际类型。
(1)要求类成员函数在类外定义。
(2)在此基础上,再实现减法、乘法和除法
你可以使用的main()函数如下。
int main( )
{ Complex<int> c1(3,4),c2(5,-10),c3;
c3=c1.complex_add(c2);
cout<<"c1+c2=";
c3.display( );
Complex<double> c4(3.1,4.4),c5(5.34,-10.21),c6;
c6=c4.complex_add(c5);
cout<<"c4+c5=";
c6.display( );
system("pause");
return 0;
}
附:例10.1的代码
#include <iostream>
using namespace std;
class Complex
{
public:
Complex( ){real=0;imag=0;}
Complex(double r,double i){real=r;imag=i;}
Complex complex_add(Complex &c2);
void display( );
private:
double real;
double imag;
};
Complex Complex::complex_add(Complex &c2)
{
Complex c;
c.real=real+c2.real;
c.imag=imag+c2.imag;
return c;
}
void Complex::display( )
{
cout<<"("<<real<<","<<imag<<"i)"<<endl;
}
int main( )
{
Complex c1(3,4),c2(5,-10),c3;
c3=c1.complex_add(c2);
cout<<"c1="; c1.display( );
#include <iostream>
using namespace std;
template <class numtype>
class Complex
{
public:
Complex( ){real=0;imag=0;}
Complex(double r,double i){real=r;imag=i;}
Complex complex_add(Complex &c2);
Complex complex_subtract(Complex <numtype> &c2);
Complex complex_multiply(Complex <numtype> &c2);
Complex complex_divide(Complex <numtype> &c2);
void display( );
private:
double real;
double imag;
};
template <class numtype>
Complex<numtype> Complex<numtype>::complex_add(Complex <numtype> &c2)
{
Complex <numtype> c;
c.real=real+c2.real;
c.imag=imag+c2.imag;
return c;
}
template <class numtype>
Complex<numtype> Complex<numtype>::complex_subtract(Complex <numtype> &c2)
{
Complex <numtype> c;
c.real=real-c2.real;
c.imag=imag-c2.imag;
return c;
}
template <class numtype>
Complex<numtype> Complex<numtype>::complex_multiply(Complex <numtype> &c2)
{
Complex <numtype> c;
c.real=real*c2.real-imag*c2.imag;
c.imag=imag*c2.real+real*c2.imag;
return c;
}
template <class numtype>
Complex<numtype> Complex<numtype>::complex_divide(Complex <numtype> &c2)
{
Complex <numtype> c;
c.real=(real*c2.real+c2.imag*imag)/(real*real+imag*imag);
c.imag=(c2.imag*real-c2.real*imag)/(real*real+imag*imag);
return c;
}
template <class numtype>
void Complex<numtype>::display( )
{
cout<<"("<<real<<","<<imag<<"i)"<<endl;
}
int main( )
{
Complex<int> c1(3,4),c2(5,-10),c3;
c3=c1.complex_add(c2);
cout<<"c1+c2=";
c3.display( );
c3=c1.complex_subtract(c2) ;
cout<<"c1-c2=";
c3.display( );
c3=c1.complex_multiply(c2);
cout<<"c1*c2=";
c3.display( );
c3=c1.complex_divide(c2);
cout<<"c2/c1=";
c3.display( );
Complex<double> c4(3.1,4.4),c5(5.34,-10.21),c6;
c6=c4.complex_add(c5);
cout<<"c4+c5=";
c6.display( );
c6=c4.complex_subtract(c5) ;
cout<<"c4-c5=";
c6.display( );
c6=c4.complex_multiply(c5);
cout<<"c4*c5=";
c6.display( );
c6=c4.complex_divide(c5) ;
cout<<"c5/c4=";
c6.display( );
system("pause");
return 0;
}
感言:掌握了类模板这个程序没有太大难度。
但在public里作声明时还有必要加上
Complex complex_subtract(Complex <numtype> &c2);
Complex complex_multiply(Complex <numtype> &c2);
Complex complex_divide(Complex <numtype> &c2);
中的<numtype>吗?